257 research outputs found
51P Interleukina – 6 i rozpuszczalny receptor Interlekiny – 6 u chorych na raka jajnika
Celem pracy była ocena stężeń Interleukina – 6 (IL-6) oraz rozpuszczalnego receptora Interleukiny – 6 (slL-6) u chorych na raka jajnika przed rozpoczęciem leczenia oraz przed 3 kursem leczenia chemicznego oraz odpowiedź na pytanie czy mogą one stanowić czynniki rokowniczy w raku jajnika.Badaniu poddano 20 chorych, leczenie rozpoczęto w Katedrze Onkologii AM w Poznaniu w latach 1990–1996. Leczenie chorych rozpoczęto od rozpoznania nowotworu poprzez pierwotne leczenie operacyjne i następową chemioterapie opartą o analogii platyny. W przypadku chorych pozostających w leczeniu oraz chorych, które znajdują się w całkowitej remisji potwierdzonej histopatologicznie operacja “second-look” obserwację kontynuowano do 36 miesięcy od chwili rozpoczęcia leczenia. W grupie badanej 3 chore miały I stopień klinicznego zaawansowania wg FIGO, natomiast pozostałe III i IV stopień złośliwości zróżnicowania komórkowego, 8 stopień II, a 10 stopień III. Histopatologiczne typy raka jajnika w grupie badanej były następujące: u 8 chorych rozpoznano typ surowiczny, u 5 endometroidalny, u 3 śluzowy, natomiast u pozostałych 4 chorych rozpoznano po jednym typie raka mezonefroidalnego, niezróżnicowanego, adenocarcinoma oraz cystadeno-carcinoma.Do momentu zakończenia obserwacji 13 chorych zmarło z powodu choroby. W chwili zakończenia obserwacji żyje 7 chorych: 5 pozostaje w leczeniu a 2 pod obserwacją bez objawów choroby.U każdej chorej przed rozpoczęciem leczenia operacyjnego oraz przed 3 kursem chemioterapii pobierano krew, którą po skrzepnięciu i odwirowaniu zamrażano do czasu wykonania oznaczeń. Interleukinę-6 (IL-6) oraz rozpuszczalny receptor lnterleukiny-6 (sIL-6) oznaczano za pomocą testów immunoenzymatycznych firmy R&D Systems.Oceniono zmiany w stężeniu powyższych parametrów w zależności od stopnia klinicznego zaawansowania wg FIGO, gradingu, rodzaju przeprowadzonego zabiegu operacyjnego, typu histologicznego nowotworu oraz odpowiedzi na leczenie.Stężenia IL-6 przed rozpoczęciem leczenia operacyjnego u 3 chorych było poniżej 3,13 pg/ml, u 9 nie przekraczało 12,5 pg/ml, a u pozostałych 8 chorych przekraczało 12,5 pg/ml (górna granica normy), natomiast przed 3 kursem chemioterapii u 10 chorych było poniżej 3,13 pg/ml, u 8 nie przekraczało 12,5 pg/ml, a jedynie u 2 przekraczało 12,5 pg/ml.Stężenia slL-6 przed rozpoczęciem leczenia operacyjnego u wszystkich chorych było prawidłowe (14–46 ng/ml) a przed 3 kursen chemioterapii przekraczało normę jedynie u jednej osoby.Obserwowano zmniejszenie się stężenia IL-6 w trakcie leczenia. Średnie stężenie IL-6 przed rozpoczęciem leczenia operacyjnego wynosiło 25,51 pg/ml (min 2,02pg/ml, max 134,25 pg/ml) i uległo zmniejszeniu przed 3 kursem chemioterapii średnio do 4,80 pg/ml (min 0,82 pg/ml, max 30,36 pg/ml) w sposób ststystycznie istotny.Nie obserwowano natomiast żadnych istotnie statystycznie zmian w odniesieniu do slL-6. Średnie stężenie slL-6 przed rozpoczęcie4m. leczenia operacyjnego wynosiło 28,44 ng/ml (min 17,00 ng/ml, max 45,00 ng/ml) i nie uległo w sposób istotny statystycznie zmniejszeniu przed 3 kursem chemioterapii, gdzie średnio wnsiło 28,43 ng/ml (min 19,20 ng/ml, max 50,80 ng/ml).Nie obserwujemy statystycznie istotnych zależności stężeń IL-6 i slL-6 od stopnia klinicznego zaawansowania wg FIGO, gradingu, rodzaju przeprowadzonego zabiegu operacyjnego, typu histologicznego nowotworu oraz odpowiedzi na leczenie
The origin of the first neutron star -- neutron star merger
The first neutron star-neutron star (NS-NS) merger was discovered on August
17, 2017 through gravitational waves (GW170817) and followed with
electromagnetic observations. This merger was detected in an old elliptical
galaxy with no recent star formation. We perform a suite of numerical
calculations to understand the formation mechanism of this merger. We probe
three leading formation mechanisms of double compact objects: classical
isolated binary star evolution, dynamical evolution in globular clusters and
nuclear cluster formation to test whether they are likely to produce NS-NS
mergers in old host galaxies. Our simulations with optimistic assumptions show
current NS-NS merger rates at the level of 10^-2 yr^-1 from binary stars, 5 x
10^-5 yr^-1 from globular clusters and 10^-5 yr^-1 from nuclear clusters for
all local elliptical galaxies (within 100 Mpc^3). These models are thus in
tension with the detection of GW170817 with an observed rate 1.5 yr^-1 (per 100
Mpc^3; LIGO/Virgo estimate). Our results imply that either (i) the detection of
GW170817 by LIGO/Virgo at their current sensitivity in an elliptical galaxy is
a statistical coincidence; or that (ii) physics in at least one of our three
models is incomplete in the context of the evolution of stars that can form
NS-NS mergers; or that (iii) another very efficient (unknown) formation channel
with a long delay time between star formation and merger is at play.Comment: A&A: accepte
Noninteracting Black Hole Binaries with Gaia and LAMOST
Until recently, black holes (BHs) could be discovered only through accretion
from other stars in X-ray binaries, or in merging double compact objects.
Improvements in astrometric and spectroscopic measurements have made it
possible to detect BHs also in non-interacting BH binaries (nBHB) through a
precise analysis of the companion's motion. In this study, using an updated
version of the Startrack binary-star population modelling code and a detailed
model of the Milky Way (MW) galaxy we calculate the expected number of
detections for Gaia and LAMOST surveys. We develop a formalism to convolve the
binary population synthesis output with a realistic stellar density
distribution, star-formation history (SFH), and chemical evolution for the MW,
which produces a probability distribution function of the predicted
compact-binary population over the MW. This avoids the additional statistical
uncertainty which is introduced by methods which Monte Carlo sample from binary
population synthesis output to produce one potential specific realisation of
the MW compact-binary distribution, and our method is also comparatively fast
to such Monte Carlo realisations. Specifically, we predict - nBHBs
to be observed by Gaia, although the numbers may drop to - if the
recent ( Myr) star formation is low (/yr ). For
LAMOST we predict detectable nBHBs, which is lower partially
because its field-of-view covers just of the Galaxy.Comment: 23 pages, 15 figures, 8 table
Flow cytometry of DNA content in ductable breast carcinoma
The measurements of DNA content and analysis of neoplastic cells cycle may have significance in diagnostic, prognostic and therapeutic management.The occurence of aneuploid cells in investigative material is usually connected with poor prognosis.In our research study the results of flow cytometry measurement have been compared with histopatological grade, tumor volume and lymph nodes status.The investigative samples (n-40) came from women, who underwent operation in 1994–1995 in Center of Oncology, Poznań. The cells for flow cytometry analysis were isolated from tumores (mastectomy) by enzymatic method (pepsin).The measurement has been performed on flow cytometer. Cytron Absolute Ortho after dyeing the cells by propidium iodide.Aneuploid cells occured in 77.5% investigative tumors. The increase in percentage on samples with abnormal content of DNA in poorly differentied tumors (G3) has been observrd. (Bloom and Richardson Classification). The percentage of aneuploid cells increased also in tumors classified as pT3 and pT4.The correlation between DNA – ploidy and lymph nodes status has not been proved.The research results indicate the significance of flow cytometry measurement of DNA content in oncological diagnostic as addition to routine
The effect of pair-instability mass loss on black-hole mergers
Context. Mergers of two stellar-origin black holes are a prime source of gravitational waves and are under intensive investigation. One crucial ingredient in their modeling has been neglected: pair-instability pulsation supernovae with associated severe mass loss may suppress the formation of massive black holes, decreasing black-hole-merger rates for the highest black-hole masses.
Aims. We demonstrate the effects of pair-instability pulsation supernovae on merger rate and mass using populations of double black-hole binaries formed through the isolated binary classical evolution channel.
Methods. The mass loss from pair-instability pulsation supernova is estimated based on existing hydrodynamical calculations. This mass loss is incorporated into the StarTrack population synthesis code. StarTrack is used to generate double black-hole populations with and without pair-instability pulsation supernova mass loss.
Results. The mass loss associated with pair-instability pulsation supernovae limits the Population I/II stellar-origin black-hole mass to 50 M⊙, in tension with earlier predictions that the maximum black-hole mass could be as high as 100 M⊙. In our model, neutron stars form with mass 1−2 M⊙. We then encounter the first mass gap at 2−5 M⊙ with the compact object absence due to rapid supernova explosions, followed by the formation of black holes with mass 5−50 M⊙, with a second mass gap at 50−135 M⊙ created by pair-instability pulsation supernovae and by pair-instability supernovae. Finally, black holes with masses above 135 M⊙ may potentially form to arbitrarily high mass limited only by the extent of the initial mass function and the strength of stellar winds. Suppression of double black-hole-merger rates by pair-instability pulsation supernovae is negligible for our evolutionary channel. Our standard evolutionary model, with the inclusion of pair-instability pulsation supernovae and pair-instability supernovae, is fully consistent with the Laser Interferometric Gravitational-wave Observatory (LIGO) observations of black-hole mergers: GW150914, GW151226, and LVT151012. The LIGO results are inconsistent with high (≳ 400 km s-1) black hole (BH) natal kicks. We predict the detection of several, and up to as many as ~60, BH-BH mergers with a total mass of 10−150 M⊙ (most likely range: 20−80 M⊙) in the forthcoming ~60 effective days of the LIGO O2 observations, assuming the detectors reach the optimistic target O2 sensitivity
Polarization due to rotational distortion in the bright star Regulus
This is the full published article (retrieved from the 6 months post-publication posting on arXiv) including the Methods and Supplementary Information sections: 33 pages, 10 figures, 8 tablesPolarization in stars was first predicted by Chandrasekhar [1] who calculated a substantial linear polarization at the stellar limb for a pure electron-scattering atmosphere. This polarization will average to zero when integrated over a spherical star but could be detected if the symmetry is broken, for example by the eclipse of a binary companion. Nearly 50 years ago, Harrington and Collins [2] modeled another way of breaking the symmetry and producing net polarization - the distortion of a rapidly rotating hot star. Here we report the first detection of this effect. Observations of the linear polarization of Regulus, with two different high-precision polarimeters, range from +42 parts-per-million (ppm) at a wavelength of 741 nm to -22 ppm at 395 nm. The reversal from red to blue is a distinctive feature of rotation-induced polarization. Using a new set of models for the polarization of rapidly rotating stars we find that Regulus is rotating at 96.5(+0.6/-0.8)% of its critical angular velocity for breakup, and has an inclination greater than 76.5 degrees. The rotation axis of the star is at a position angle of 79.5+/-0.7 degrees. The conclusions are independent of, but in good agreement with, the results of previously published interferometric observations of Regulus [3]. The accurate measurement of rotation in early-type stars is important for understanding their stellar environments [4], and course of their evolution [5].Peer reviewedFinal Accepted Versio
Dynamical Mass Measurement of the Young Spectroscopic Binary V343 Normae AaAb Resolved With the Gemini Planet Imager
We present new spatially resolved astrometry and photometry from the Gemini
Planet Imager of the inner binary of the young multiple star system V343
Normae, which is a member of the beta Pictoris moving group. V343 Normae
comprises a K0 and mid-M star in a ~4.5 year orbit (AaAb) and a wide 10" M5
companion (B). By combining these data with archival astrometry and radial
velocities we fit the orbit and measure individual masses for both components
of M_Aa = 1.10 +/- 0.10 M_sun and M_Ab = 0.290 +/- 0.018 M_sun. Comparing to
theoretical isochrones, we find good agreement for the measured masses and JHK
band magnitudes of the two components consistent with the age of the beta Pic
moving group. We derive a model-dependent age for the beta Pic moving group of
26 +/- 3 Myr by combining our results for V343 Normae with literature
measurements for GJ 3305, which is another group member with resolved binary
components and dynamical masses.Comment: 12 pages, 7 figures. Accepted to A
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